This application claims the benefit of priority of FR Application No. 99 13791, filed Nov. 4, 1999, entitled Naphthopyrans With A Heterocycle In The 5,6-Position, Preparation, And (Co)Polymer Compositons And Matrices Containing Them, of Breyne et al.
The present invention relates to novel compounds of the fused naphthopyran type which have photochromic properties in particular. It further relates to the photochromic compositions and photochromic ophthalmic articles (for example lenses) containing said naphthopyrans. The invention further encompasses the preparation of these novel compounds.
Photochromic compounds are capable of changing color under the influence of a poly- or monochromatic light (for example UV) and of returning to their initial color when the light irradiation ceases or under the influence of temperature and/or a different poly- or monochromatic light from the first.
Photochromic compounds are applicable in various fields, for example for the manufacture of ophthalmic lenses, contact lenses, sunglasses, filters, optics for movie cameras, ordinary cameras or other optical and observational devices, glass panes, decorative objects or display elements, or for the storage of data by optical recording (coding).
In the field of ophthalmic optics and particularly spectacles, a photochromic lens, comprising one or more photochromic compounds, must have:
a high transmission in the absence of ultraviolet,
a low transmission (high colorability) under solar irradiation,
appropriate coloration and decolorization kinetics,
a tint acceptable to the consumer (preferably gray or brown), preferably with maintenance of the chosen tint during the coloration and decolorization of the lens,
maintenance of the performance characteristics and the properties over the temperature range 0-40xc2x0 C., and
a substantial durability because the intended objectives are sophisticated and hence expensive corrective lenses.
These lens characteristics are in fact determined by the active photochromic compounds which the lens contains, it also being necessary for said compounds to be perfectly compatible with the organic, mineral or even hybrid substrate of which the lens is made.
It should furthermore be noted that, to obtain a gray or brown tint, it may be necessary to use at least two photochromic substances of different colors, i.e. having different maximum absorption wavelengths in the visible. This association makes yet more demands on the photochromic compounds. In particular, the coloration and decolorization kinetics of the (two or more) associated active photochromic compounds must be substantially identical. The same applies to their stability over time and also to their compatibility with a plastic or mineral substrate.
The benzopyrans or naphthopyrans described in the following patents or patent applications may be mentioned among the numerous photochromic compounds described in the prior at: U.S. Pat. No. 3,567,605, U.S. Pat. No. 3,627,690, U.S. Pat. No. 4,826,977, U.S. Pat. No. 5,200,116, U.S. Pat. No. 5,238,981, U.S. Pat. No. 5,411,679, U.S. Pat. No. 5,429,744, U.S. Pat. No. 5,451,344, U.S. Pat. No. 5,458,814, U.S. Pat. No. 5,651,923, U.S. Pat. No. 5,645,767, U.S. Pat. No. 5,698,141, U.S. Pat. No. 5,783,116, WO-A-95 05382, FR-A-2 718 447, WO-A-96 14596 and WO-A-97 21698, said compounds having the reduced formulae below: 
U.S. Pat. No. 5,783,116 more specifically describes naphthopyrans of the following general structure: 
U.S. Pat. No. 5,811,034 claims the following general structure in particular: 
These compounds are said to satisfy the specifications defined above. In reality, although these compounds do indeed have one or more of the desired basic properties, such as a high transmission in the absence of ultraviolet and a high colorability under solar irradiation, none of the compounds described hitherto have the complete combination of desired properties which is necessary for the production of satisfactory articles. In particular, none of these compounds is intrinsically gray or brown and there is still a need to use a complementary photochromic substance in order to obtain one of these two tints.
In this context, it is to the inventors"" credit that they took an interest in this type of derivative as a basis for the development of novel photochromic substances, and that they are proposing a novel family of molecules possessing particularly advantageous photochromic properties.
Thus, according to a first feature, the present invention relates to compounds of formula (I) or (II): 
in which:
X is an oxygen or NR6, R6 being a hydrogen, a linear or branched alkyl group containing from 1 to 12 carbon atoms, a cycloalkyl group containing from 3 to 12 carbon atoms or an aryl or heteroaryl group containing in its basic structure 6 to 24 carbon atoms or, respectively, 4 to 24 carbon atoms and at least one heteroatom selected from sulfur, oxygen and nitrogen, said basic structure optionally being substituted by at least one substituent selected from a linear or branched alkyl containing 1 to 12 carbon atoms, a linear or branched alkoxy containing 1 to 12 carbon atoms, a halogen and a hydroxy;
R4 and R5, which are identical or different, independently are a hydrogen, a hydroxy or a linear or branched alkyl group containing 1 to 6 carbon atoms, or together form an oxo group (xe2x95x90O);
R1 and R2, which are identical or different, independently are:
hydrogen,
a linear or branched alkyl group containing from 1 to 12 carbon atoms,
a cycloalkyl group containing from 3 to 12 carbon atoms,
an aryl or heteroaryl group containing in its basic structure 6 to 24 carbon atoms or, respectively, 4 to 24 carbon atoms and at least one heteroatom selected from sulfur, oxygen and nitrogen, said basic structure optionally being substituted by at least one substituent selected from the group of substituents given below:
a halogen, especially fluorine, chlorine or bromine,
a hydroxy,
a linear or branched alkyl group containing from 1 to 12 carbon atoms,
a linear or branched alkoxy group containing from 1 to 12 carbon atoms,
a haloalkyl or haloalkoxy group corresponding respectively to the above (C1-C12)alkyl or (C1-C12)alkoxy groups substituted by at least one halogen atom, especially a fluoroalkyl group of this type,
a phenoxy or naphthoxy group optionally substituted by at least one linear or branched alkyl or alkoxy group containing from 1 to 12 carbon atoms,
a linear or branched alkenyl group containing from 2 to 12 carbon atoms, especially the vinyl group or the allyl group,
a group xe2x80x94NH2,
a group xe2x80x94NHR, R being a linear or branched alkyl group containing from 1 to 6 carbon atoms or a phenyl optionally substituted by at least one linear or branched alkyl containing from 1 to 6 carbon atoms,
a group: 
xe2x80x83Rxe2x80x2 and Rxe2x80x3, which are identical or different, independently being a linear or branched alkyl group containing from 1 to 6 carbon atoms or a phenyl optionally substituted by at least one linear or branched alkyl containing 1 to 6 carbon atoms, or, together with the nitrogen atom to which they are bonded, being a 5- to 7-membered ring which can contain at least one other heteroatom selected from oxygen, sulfur and nitrogen, said nitrogen optionally being substituted by a group Rxe2x80x2xe2x80x3, which is a linear or branched alkyl group containing from 1 to 6 carbon atoms, or
a methacryloyl group or an acryloyl group,
an aralkyl or heteroaralkyl group in which the alkyl group is linear or branched and contains from 1 to 4 carbon atoms and in which the aryl or heteroaryl moiety is as defined above for the aryl or heteroaryl group, or
said two substituents R1 and R2 together form an adamantyl, norbornyl, fluorenylidene, di(C1-C6)alkylanthracenylidene or spiro(C5-C6)cycloalkylanthracenylidene group, said group optionally being substituted by at least one of the substituents listed above for R1 and R2 as an aryl or heteroaryl group;
R3, which are identical or different, independently are:
a halogen, especially fluorine, chlorine or bromine,
a hydroxy,
a linear or branched alkyl group containing from 1 to 12 carbon atoms (advantageously from 1 to 6 carbon atoms),
a cycloalkyl group containing from 3 to 12 carbon atoms,
a linear or branched alkoxy group containing from 1 to 12 carbon atoms (advantageously from 1 to 6 carbon atoms),
a haloalkyl, halocycloalkyl or haloalkoxy group corresponding respectively to the above alkyl, cycloalkyl and alkoxy groups substituted by at least one halogen atom selected especially from fluorine, chlorine and bromine,
an aryl or heteroaryl group as defined above for R1 and R2,
an aralkyl or heteroaralkyl group, the alkyl group, which is linear or branched, containing from 1 to 4 carbon atoms and the aryl and heteroaryl a groups being as defined above for R1 and R2,
a phenoxy or naphthoxy group optionally substituted by at least one linear or branched alkyl or alkoxy group containing from 1 to 12 carbon atoms,
one of the following amine or amide groups: xe2x80x94NH2, xe2x80x94NHR, xe2x80x94CONH2, xe2x80x94CONHR, 
xe2x80x83R, Rxe2x80x2 and Rxe2x80x3 respectively being as defined above for the amino substituents of R1 and R2 as aryl or heteroaryl, or
a group xe2x80x94OCOR7 or xe2x80x94COOR7, R7 being a linear or branched alkyl group containing from 1 to 6 carbon atoms, a cycloalkyl group containing from 3 to 6 carbon atoms or a phenyl group, optionally substituted by at least one of the substituents listed above for R1 and R2 as aryl or heteroaryl, or
at least two adjacent groups R3 together form an aromatic or non-aromatic cyclic group with one ring or two fused rings, which can contain at least one heteroatom selected from the group comprising oxygen, sulfur and nitrogen, it being possible for said ring(s), which are independently aromatic or non-aromatic and 5- to 7-membered, to contain at least one substituent selected from a group as defined above by way of substituents of the basic structure of the aryl or heteroaryl group representing R1 or R2; and
m is an integer from 0 to 4.
Those skilled in the art will obviously have understood that the branched alkyl, alkoxy and alkenyl groups as defined above contain a sufficient number of carbons to be able to be branched (respectively more than 3, more than 3 and more than 4 carbon atoms).
The compounds of the inventionxe2x80x94naphthopyrans of formula (I) or (II)xe2x80x94possess a high colorability associated with decolorization kinetics appropriate to the intended applications. The colors, which are readily accessible, vary from orange to violet.
Among said compounds of formula (I) or (II) of the invention, there are those in which:
X is an oxygen. Among these compounds, the following two subfamilies are very particularly preferred: the subfamily of compounds of formula (I) or (II) in which X=O, as stated, and R4 and R5 together form an oxo group, and the subfamily of compounds of formula (I) or (II) in which X=O, as stated, and R4 and R5 are hydrogens; and those in which:
X is a group NR6. Among these compounds, the following three subfamilies are very particularly preferred: the subfamily of compounds of formula (I) or (II) in which X=NR6, as stated, and R4 and R5 together form an oxo group, the subfamily of compounds of formula (I) or (II) in which X=NR6, as stated, and R4 and R5 are hydrogens, and the subfamily of compounds of formula (I) or (II) in which X=NR6, as stated, R4 is a hydrogen and R5 is a hydroxy.
With reference to the substituents R1 and R2, the preferred compounds of formula (I) or (II) are those in which:
R1 and R2 are identical or different and independently are optionally substituted aryl or heteroaryl groups whose basic structure is selected from the group comprising phenyl, naphthyl, biphenyl, pyridyl, furyl, benzofuryl, dibenzofuryl, N-(C1-C6)alkylcarbazole, thienyl, benzothienyl, dibenzothienyl and julolidinyl groups, R1 and/or R2 advantageously being a para-substituted phenyl group; or those in which:
R1 and R2 together form an adamantyl or norbornyl group.
In a first embodiment of the invention, the compounds (I) or (II) are such that at least two of their adjacent substituents R3 do not together form a ring.
In a second embodiment of the invention, the compounds (I) and (II) are such that they comprise at least two adjacent groups R3 which together form an aromatic or non-aromatic cyclic group with one ring or two fused rings, which can contain at least one heteroatom selected from the group comprising oxygen, sulfur and nitrogen, it being possible for said ring(s), which independently are aromatic or non-aromatic and 5- to 7-membered, to contain at least one substituent selected from a group as defined above by way of substituents of the basic structure of the aryl or heteroaryl group representing R1 or R2.
The compounds of the invention can be synthesized according to the following general scheme: 
R1, R2, R3, R6 and m being as defined above with reference to formulae (I) and (II).
The starting materials A can be obtained by a procedure described by Kotsuki et al. (Bull. Chem. Soc. Jpn. 1994, 67, 599).
The intermediates B are obtained by processes well known to those skilled in the art (cf. e.g. EP-A-0 562 915 and U.S. Pat. No. 5,793,116).
The compounds C according to the invention are obtained by saponification of the esters in a basic medium, followed by a thermal cyclization-dehydration.
The compounds D according to the invention are obtained by condensing compounds C with a primary amine.
The other compounds of the invention in which R4 and/or R5=H or OH are obtained by reducing compounds C or D. Controlled reduction of the anhydrides (compounds C) with hydrides, such as NaBH4 or LiAlH4, yields lactones (R4 and R5=H) and/or hydroxyactones (R4=H and R5=OH) and controlled reduction of the imides yields lactams (R4 and R5=H) or hydroxyactams (R4=H and R5=OH) (cf. e.g. the following references: Bailey and Johnson, J. Org. Chem. 1970, 35, 3574 and Sato et al., Bull. Chem. Soc. Jpn. 1988, 61, 2238). Likewise, the anhydride or the imide is reacted with one or two equivalents of an organo-magnesium compound (alkylMgBr) to give the derivatives in which R4=OH and R5=alkyl or R4=R5=alkyl (cf. e.g. Zhang et al., J. Amer. Chem. Soc. 1993, 115, 3670-3673). The compounds in which R4=H and R5=alkyl (X=O or NR6) can be synthesized according to the chemistry described by Canonne et al. in Tetrahedron 1988, 44, 2903.
According to a third feature, the invention relates to (co)polymers and/or crosslinked products obtained by the polymerization and/or crosslinking and/or grafting of at least one compound (I) or (II) as defined above. The compounds (I) or (II) according to the invention can be (co)monomers per se and/or can be included in (co)polymerizable and/or crosslinkable (co)monomers. The (co)polymers and/or crosslinked products obtained in this way can constitute photochromic matrices such as those presented below.
According to a fourth feature, the present invention relates to the use of said compounds of formula (I) or (II) of the invention as photochromic agents. The invention therefore further relates:
on the one hand to novel photochromic compounds which consist of the naphthopyran derivatives as defined above, taken in isolation or in a mixture with one another and/or with at least one other photochromic compound of a different type and/or with at least one non-photochromic coloring agent; and
on the other hand to novel photochromic compositions which comprise at least one compound (I) or (II), as defined above, and/or at least one linear or crosslinked (co)polymer containing in its structure at least one compound (I) or (II) according to the invention. Such photochromic compositions can contain at least one other photochromic compound of a different type and/or at least one non-photochromic coloring agent and/or at least one stabilizer. These photochromic compounds of a different type, non-photochromic coloring agents and stabilizers are products of the prior art known to those skilled in the art.
Associations of photochromic compounds of the invention and/or associations of photochromic compounds of the invention and photochromic compounds of a different type, according to the prior art, are particularly recommended within the framework of the present invention, such associations being of value in that they are suitable for generating the gray or brown tints sought after by the public in applications such as ophthalmic lenses or sunglasses. These complementary photochromic compounds can be the ones known to those skilled in the art and described in the literature, for example chromenes (U.S. Pat. No. 3,567,605, U.S. Pat. No. 5,238,981, WO-A-94 22850, EP-A-0 562 915), spiropyrans or naphthospiropyrans (U.S. Pat. No. 5,238,981) and spiroxazines (CRANO et al., xe2x80x9cApplied Photochromic Polymer Systemsxe2x80x9d, published by Blackie and Son Ltd, 1992, chapter 2).
Said compositions according to the invention can also contain:
non-photochromic coloring agents for adjusting the tint,
and/or one or more stabilizers, for example an antioxidant,
and/or one or more UV inhibitors,
and/or one or more free radical inhibitors,
and/or one or more deactivators of photochemical excited states.
These additives can make it possible in particular to improve the durability of said compositions.
The compounds of the invention, envisaged within the framework of their photochromic applications, can be used in solution. Thus a photochromic solution can be obtained by solubilizing at least one of said compounds in an organic solvent such as toluene, dichloromethane, tetrahydrofuran or ethanol. The solutions obtained are generally colorless and transparent. They develop a strong coloration when exposed to sunlight and return to the colorless state when placed in a zone of lower exposure to solar radiation or, in other words, when they are no longer subjected to UV. A very low concentration of product (of the order of 0.01 to 5% by weight) is generally sufficient to obtain an intense coloration.
Furthermore, the compounds according to the invention are compatible with substrate matrices made of organic polymer or mineral (even hybrid) material, either included in said matrices or coated on said matrices.
Therefore, within the framework of the fourth feature of the invention pertaining to photochromic applications, the invention relates to a matrix containing:
at least one compound (I) or (II) as defined above,
and/or at least one (co)polymer and/or crosslinked product as defined above,
and/or at least one composition as presented above.
In fact, the most advantageous applications of the compounds of the invention are those in which the photochromic substance is uniformly dispersed within or over the surface of a matrix formed by a polymer and/or a copolymer and/or a mixture of (co)polymers.
Mirroring their behavior in solution, the compounds (I) or (II) included in a polymer matrix are colorless or slightly colored in the initial state and rapidly develop an intense coloration under UV light (365 nm) or a light source of the solar type. Finally, they return to their initial color when the irradiation ceases.
The processes which can be envisaged for obtaining such a matrix are very varied. An example which may be mentioned among the processes known to those skilled in the art is diffusion of the photochromic substance into the (co)polymer from a suspension or solution in a silicone oil, an aliphatic or aromatic hydrocarbon or a glycol, or from another polymer matrix. The diffusion is commonly carried out at a temperature of 50 to 200xc2x0 C. for a period of 15 minutes to a few hours, depending on the nature of the polymer matrix. Another practical technique consists in mixing the photochromic substance into a formulation of polymerizable substances, depositing this mixture on a surface or in a mold and then performing the copolymerization. These and other practical techniques are described in the article by CRANO et al. entitled xe2x80x9cSpiroxazines and their use in photochromic lensesxe2x80x9d in Applied Photochromic Polymer Systems, published by Blackie and Son Ltdxe2x80x941992.
The following products may be mentioned as examples of preferred polymer materials for forming matrices which can be used in optical applications of the photochromic compounds according to the invention:
alkyl, cycloalkyl, (poly or oligo)ethylene glycol, aryl or arylalkyl mono-, di-, tri- or tetraacrylate or mono-, di-, tri- or tetramethacrylate which is optionally halogenated or contains at least one ether and/or ester and/or carbonate and/or carbonate and/or thiocarbamate and/or urea and/or amide group,
polystyrene, polyether, polyester, polycarbonate (e.g. polybisphenol-A carbonate, polydiallyldiethylene glycol carbonate), polycarbamate, polyepoxide, polyurea, polyurethane, polythiourethane, polysiloxane, polyacrylonitrile, polyamide, aliphatic or aromatic polyester, vinylic polymers, cellulose acetate, cellulose triacetate, cellulose acetate-propionate or polyvinylbutral,
those obtained from difunctional monomers of the following formula: 
in which:
R10, Rxe2x80x210, R11 and Rxe2x80x211 are identical or different and independently are a hydrogen or a methyl group,
m1 and n1 independently are integers between 0 and 4 inclusive and advantageously are independently equal to 1 or 2,
X and Xxe2x80x2, which are identical or different, are a halogen, preferably a chlorine and/or a bromine, and
p1 and q1 independently are integers between 0 and 4 inclusive, or
copolymers of at least two types of copolymerizable monomers selected from the monomers which are precursors of the polymers listed above, preferably those belonging to the groups comprising (meth)acrylic, vinylic and allylic monomers and mixtures thereof.
Particularly preferably, the photochromic substances of the invention are used with resins which have a nanobiphase structure and are obtained by copolymerizing at least two specific, different difunctional monomers. Such resins have been described by the Applicant in patent application FR-A-2 762 845.
The amount of photochromic substance used in the (co)polymer matrix depends on the desired degree of darkening. The amount used is normally between 0.001 and 20% by weight.
Again according to the fourth feature pertaining to applications of the compounds (I) or (II) as photochromic substances, the present invention further relates to ophthalmic articles, such as ophthalmic lenses or sunglasses, comprising:
at least one compound (I) or (II) according to the invention,
and/or at least one (co)polymer and/or crosslinked product at least partially formed by at least one compound of the invention,
and/or at least one photochromic composition as defined above,
and/or at least one matrix (as defined above) made of an organic polymer, a mineral material or a mineral-organic hybrid material, said matrix optionally comprising initially at least one compound of the invention.
In practice, the articles to which the present invention relates more particularly are photochromic ophthalmic lenses or sunglasses, glass panes (windows for buildings, locomotive engines, automotive vehicles), optical devices, decorative articles, articles for solar protection, data storage, etc.